Floating lift station

ABSTRACT

A sewer system for a floating wharf utilizing a floating lift station. Means are provided for gravity feeding sewage from a plurality of floating boat slips to a floating holding tank at the lift station, and means are provided for transferring sewage from the holding tank to a main sewage conduit.

United States Patent 444,007 I/] 891 Monjeau Inventor Kenneth L.Thompson Huntington Beach, Calif. Appl. No. 818,658 Filed Apr. 23, 1969Patented Jan. 5, 1971 Assignee Ye Dock Master, Inc.

a corporation of California FLOATING LIFT STATION 12 Claims, 4 DrawingFigs.

[1.8. (I 137/343, 4/10; ll4/0.5(F) Int. Cl F161 5/00 Field ofSearch2l4/12; l|4/0.5(F),2l0/242;4/l0. 15; 137/344 References Cited UNITEDSTATES PATENTS Primary Examiner-Samuel Scott Atlomey-Nilsson and RobbinsABSTRACT: A sewer system for a floating wharf utilizing a floating liftstation. Means are provided for gravity feeding sewage from a pluralityof floating boat slips to a floating holding tank at the lift station,and means are provided for transferring sewage from the holding tank toa main sewage conduit.

sewer system of this invention;

. f 1 FLOATING LIFT STATION BACKGROUND OF THE INVENTION 1. Field of theInvention The fields of art to which the invention pertains include thefield of sewerage and the field of ships, particularly floating dockstherefor. g k

2. Description of the Prior Art In constructing marinas or small boatharbors it isoften desirable to utilize a floating, wharf structurewhich is accessible to land and has one or more fingers extending outinto the body of water. At certainfacilities, it often occurs that theboater remains in a ;boat slip for an extended period of time duringwhich time he lives on the boat. Under such circumstances, the boaterrequires sewage disposalfacilities and it is desirable to provide suchfacilities, or access to such facilities at the boat slip. However,theprovision of sewage disposal facilities on a floating wharf structurepresents problems of construction which have heretofore generallylimited the availability of sewage disposal facilities tononfloatingstructures or to limited access areas.

SUMMARY OF THE INVENTION The present invention provides a sewagedisposal system for a floating wharf structure which allowsaccessthereto from any-of a plurality of boat slips associated with thewharf structure. In particular, a sewer system for a floatingwharfis-provided, comprising: a main sewage conduitat a first level; a

floating tank for holdingsewagebelow the first level; meansfor feedingsewage from a plurality of floating boat slips to the holding tank; andmeans for transferring sewage from the holding tank to the main sewageconduit. The's'e'wage feeding means comprises a feed conduit havingan-intake port and an exhaust, the intake port beingat a levelhigherthan the sewage in the holding tank. Means are provided forconnecting'the exhaust of the feed conduit to the holding tank'wherebysewage introduced into the feed conduitis gravity fed to the holdingtank. An intake port is provided at each of ajpluralityof boat slips,each such intake port being at a level higher than the sewage in theholding tank, toreceive sewage from said boat slips and gravity feed itto the holding tank.

The holdingtank is secured in a substantially fixed lateral positionwith respect to the'wharfbutis'allowedto moveverti cally. In particular,the holding tank is slidably'disposedwn rigid means extending downwardlyfrom the wharf-structure, and means are included for limiting theextent-of-its downward movement. The holding tank includes intake and:exhaust p'ons'forconnection to theexhau'stof the feed; conduit and tothe main sewage conduit, respectively, and is connected of the headwalkl0 and constitute a floating wharf structure. The structure is supportedon pontoons 18. (FIG. 2) and is connected to a land structure 20 bymeans of a ramp 22 extending from one end of the wharf structure to theland structure 20. The sewer system in accordance with this invention isshown by dashed lines in FIG. 1 and includes a lift station 24 intowhich sewage is fed by means-of a feed conduit 26 extending lengthwiseof the headwalk 10 which, in turn, is fed by a plurality of branchconduits 28. The branch conduits are disposed so that each boat slip 16has a branch conduit 28 associated therewith. Sewage is gravity fed intothe lift station and, as hereinafter described, is then pumped into amain sewage conduit 30 which leads into the main sewer line as indicatedby the arrow 32, Inoperation, a boater connects the disposal system ofhisboat into the branch sewer conduit 28 located at the slip in whichhisboat is docked. Upon disposing of his sewage, it is gravity fed via thefeed conduit 26 into the lift station 24, and from there it is pumpedinto the main sewage conduit 30. Referring to FIG. 2, an elevationalview of the lift station 24 and details of construction of the'wharfstructure are shown. The headwalk 10 is seen to overlie a plurality ofpontoons 18 (of which only two are shown) which are interconnected bymeans of a deck 34 (FIG. 4 common thereto and by a pair of oppositelydisposed 3 inches times 8 inches stringers 36 and 38 (FIG. 3) bridgingthe pontoons 18. v

The key structure in the lift station 24 is a holding tank constructedof fiberglass or other'waterproof, light but strong material. Referringadditionally to FIG. 3, the'holding tank 40 is providedwith a cover 42closely fit thereto, an intake port 44 and, in this case, a pair ofexhaust ports-46 and 48. A relatively short length of flexible tubing 50connects the intake port to the exhaust 52 of the feed conduit 26 notedabove. Other relatively short lengthsof flexible tubing 54 and 56connect the exhaust ports 46 and 48, respectively, to the main sewageconduit 30. A pair of submersible pumps -58 andv 60 are disposed on thebottomof the holding tank 40 .and connect respectively to the exhaustport flexible tubing sections 54 and 56, into the main sewage conduit30.

An important featureof'this invention is that, within the limits offlexure of the tubing 50,.54and 56,,the holding'tank 40 is substantiallyfree-floating in the verticahdirection, but is th'e'retoby means offlexible condu'it whereby-the holding tank is essentiallyfree-floatingwithin limits ofsuch flexure.

BRIEF DESCRIPTION OF THEDRAWINGS FIG. 1 is a plan view of afloatingwharfstrujcture utilizing a FlG.2is amelevational view ofaliftstation of thisinvention utilized in the structure' of FIG. 1takenon-theline'2-2of FIG. 'I in the direction of the arrows; 1

FIG. 3 is a partially cutaway,horizontabsectional* view of the liftstation depicted 'inFF-IG t 2, taken-on line-343 no.2, irithe directionof the'a'rrowsyand FIG. 4 is a broken, enlarged verticabsectionviewofaportion of the wharfstructure and lift station depicted inFlG.",2, taken on line 4-4 of FIG. 2; in the direction offthe arrows.

DETAILED DESCRIPTION Referring toFlG. l, there is illustratedafloatingwharf structure, including a headwalk-l0 and a plurality offinger sections 12 connected to-the headwalk" by means 'of cornersections 14. The headwalklll, -finger"sections l:2'and"corner sectionsl4 define ajpliirality of boat slips l'6 a'longf-both sides laterallyrestrained so that horizontal displacement is prevented.

"Referringto FIG. 4, there is disclosed'thermanner in which theholdingtank 40 isallowed to free-float, and other details of construction ofthe floating wharf are illustrated. The headwalk 34 of the floatingwharfis constructed of cast concrete andhasembeddedxtherein a pluralityxofthreaded nuts, such as that shown as 62:to.enablefastening.thereat'ofthestringer 36 by means of a bolt 64 therethrough; aplurality of-such bolts64 are'shown in FIG; 2. A metal,..L'-shaped* beam 66 is; disposed 1between thestringer 36 .an'd the side of theconcrete headwalk v34and-serves to stronglysupport lateral guide-members68 extendingdownwardly therefrom,'The'horizontal, lower leg of the L-shaped beam 66defines threaded openings therethrough aligned with apertures72.inthestringer36 for .threadably receivingandretaining therein'the threadedends of the latera'lwguide members'v68. Referringiback to, F-lG.2, .setsof threesuch guide members are disposedon-opposite-sides of the holding.tank 40. The'hol'ding tank 40'is provided -with a flared lip 74 which is:coex-tensive with'fthe rim.'76aofthe holding tank cover 42.An aperture'78is formed through thecoextensive lip 74 and rim"7,6and is reinforcedwith a short section of steel pipe 80 welded thereto. The.lateral-guideimembersfi8 -are:each of?anelongate.cylindricaLconfigurationand extend In operation, the holdingtank 40 is disposed beneath the walkway 34 between a pair of pontoons18, and beneath any utility lines such as shown at 84 which aresupported by the pontoons 18. The holding tank 40 is limited in itslateral movement by means of the guide members 68. However, the guidemembers 68 allow the holding tank 40 to otherwise freelyfloat on thewater. Solid ballast is provided (shown by the dashed line 86 in FIG. 2)so as to cause the holding tank 40 to float at a minimum distance belowthe headwalk 34. The walkway 10 is pitched at a small angle as a resultof the weight of the gang plank 22 so that the feed conduit 26 ispitched slightly towards the lifting station 24. Sewage is introducedinto the feed conduit 26 through a branch conduit 28 and is gravity fed,via the flexible tubing 50, into the holding tank intake port 44. Asmore sewage is introduced, the holding tank 40 submerges as the resultof the increased ballast therein until a point is reached wherein thepumps 58 and 60 are automatically actuated. Any means known to the artcan be utilized to actuate the pumps in response to an increase ofvolume of sewage in the holding tanks; for example, a simple float-ballsystem can be utilized. Upon actuation, the pumps 58 and 60 transfer thesewage from the holding tanks through its exhaust ports 46 and 48, viathe respective flexible tubing sections 54 and 56, into the main sewageconduit 30 from where it travels to the land-located main sewer line. Itwill be seen that as the holding tank 40 is lowered and raised on theguided member 68 as a result of first filling and then emptying, ndeleterious effect is manifested on the floating wharf structure sincethe holding tank 40 moves substantially independently of the wharf.

I claim:

1. A sewer system for a floating wharf, comprising:

a main sewage conduit;

a floating tank for holding sewage below a first level;

a plurality of floating boat slips;

means for feeding sewage from said boat slips to said holding tank; and

means for transferring sewage from said holding tank to said main sewageconduit.

2. The system of claim I wherein said transferring means comprises apump which is automatically actuated when said sewage in said holdingtank reaches a predetermined level therewithin to pump said sewage intosaid main sewage conduit.

3. The system of claim 1 including means for securing said holding tankin substantially fixed lateral position with respect to said wharf butallowing said holding tank to move vertically with respect to saidwharf.

4. The system of claim 1 wherein said holding tank is disposed beneathsaid wharf structure, and including rigid means extending downwardlyfrom said wharf structure and disposed in slidable relation with saidholding tank.

5. The system of claim 1 including a flexible conduit between saidholding tank and said sewage feeding means and a flexible conduitbetween said holding tank and said main sewage conduit, whereby saidholdingtank can float between predetermined limits offlexure of saidconduits.

6. The system of claim 1 including ballast means in said holding tankfor limiting the upward floating level thereof.

7. A system of claim I wherein said sewage feeding means comprises afeed conduit having an intake and an exhaust, said intake being at alevel higher than said first level, said sewer system including meansfor connecting said feed conduit exhaust to said holding tank wherebysewage introduced into said feed conduit is gravity fed to said holdingtank.

8. The system of claim 7 wherein said feed conduit has an intake port ateach of a plurality of said boat slips for enabling said feed conduit toreceive sewage therefrom, each of said intake ports being at a levelhigher than said first level.

9. A floating lift station, comprising:

a tank for holding sewage and including means defining intake andexhaust ports thereof;

means for transferring sewage from said tank through said exhaust port;and l rigid means disposed in slidable relation with said tank for

1. A sewer system for a floating wharf, comprising: a main sewageconduit; a floating tank for holding sewage below a first level; aplurality of floating boat slips; means for feeding sewage from saidboat slips to said holding tank; and means for transferring sewage fromsaid holding tank to said main sewage conduit.
 2. The system of claim 1wherein said transferring means comprises a pump which is automaticallyactuated when said sewage in said holding tank reaches a predeterminedlevel therewithin to pump said sewage into said main sewage conduit. 3.The system of claim 1 including means for securing said holding tank insubstantially fixed lateral position with respect to said wharf butallowing said holding tank to move vertically with respect to saidwharf.
 4. The system of claim 1 wherein said holding tank is disposedbeneath said wharf structure, and including rigid means extendingdownwardly from said wharf structure and disposed in slidable relationwith said holding tank.
 5. The system of claim 1 including a flexibleconduit between saiD holding tank and said sewage feeding means and aflexible conduit between said holding tank and said main sewage conduit,whereby said holding tank can float between predetermined limits offlexure of said conduits.
 6. The system of claim 1 including ballastmeans in said holding tank for limiting the upward floating levelthereof.
 7. A system of claim 1 wherein said sewage feeding meanscomprises a feed conduit having an intake and an exhaust, said intakebeing at a level higher than said first level, said sewer systemincluding means for connecting said feed conduit exhaust to said holdingtank whereby sewage introduced into said feed conduit is gravity fed tosaid holding tank.
 8. The system of claim 7 wherein said feed conduithas an intake port at each of a plurality of said boat slips forenabling said feed conduit to receive sewage therefrom, each of saidintake ports being at a level higher than said first level.
 9. Afloating lift station, comprising: a tank for holding sewage andincluding means defining intake and exhaust ports thereof; means fortransferring sewage from said tank through said exhaust port; and rigidmeans disposed in slidable relation with said tank for limiting lateralmovement thereof.
 10. The lift station of claim 9 wherein saidtransferring means comprises a pump which is automatically actuated whensaid sewage in said holding tank reaches a predetermined level to pumpsaid sewage through said exhaust port.
 11. The lift station of claim 9including flexible conduits on said intake and exhaust ports wherebysaid holding tanks can substantially free-float between predeterminedflexure limits.
 12. The lift station of claim 9 including means forlimiting downward movement of said tank.